We are using LCM and Pichinde viruses, as models, to study the synthesis of arenaviruses in tissue cultures. In general we are interested in using in vitro techniques to further the understanding of the slow virus aspects of LCM. We are studying the in vitro and in vivo efficacy, and mode of action, of several compounds which specifically interfere with arenavirus synthesis. Also under investigation are the control mechanisms of LCM and Pichinde persistently infected cells that regulate the synthesis of standard and defective virus.